function getData(endpoint, cb) {
    const XHR = new XMLHttpRequest();
    XHR.open("GET", endpoint);
    XHR.onreadystatechange = function () {
    if (this.readyState === 4 && this.status === 200) 
   {
    cb(JSON.parse(this.responseText));
   }
    };

    setTimeout(() => {
    XHR.send();
    }, Math.floor(Math.random() * 3000) + 1000);
    }

getData("./movies.json", (data) => {
 console.log(data);
 getData("./actors.json", (data) => {
 console.log(data);
 getData("./directors.json", (data) => {
 console.log(data);
 });
 });
 });